1. Field of the Invention
This invention relates to improvements in a slitter device which cuts a roll-shaped long piece rotatably supported almost horizontally by a guide holder rod into round slices with the predetermined width using a rotary cutting blade which moves back and forth perpendicular to the long piece, and more particularly to the safety control of the slitter device which immediately stops the rotation of the cutting blade or retracts the cutting blade from the guide holder rod in the preferred embodiments of the invention when the rotary cutting blade contacts the guide holder rod.
2. Prior Art
In the past, an emergency stop limit switch has been generally used for the slitter device which cuts a rotating roll-shaped long piece into round slices using a rotary cutting blade. When a return switch is defective and the cutting blade rotating at a high speed closely approaches the guide holder rod to the predetermined distance (usually 1.0 to 1.5 mm), the emergency stop limit switch is actuated to turn off the motor power supply for traversing the table and the motor power supply for rotating the cutting blade to prevent the cutting blade from contacting the guide holder rod. However, as the efficiency of cutting work increases, the rotating speed of the cutting blade becomes higher. Accordingly, in addition to the safety means for contact prevention using the limit switch, another safety control means has become demanded.